A one-dimensional triaquaeuropium(III)–1H,3H-benzimidazol-3-ium-5,6-dicarboxylate–sulfate polymeric structure

Abstract

In the title coordination polymer, catena-poly[[[triaquaeuropium(III)]-bis(μ-1H,3H-benzimidazol-3-ium-5,6-dicarboxylato-κ3O5,O5′:O6)-[triaquaeuropium(III)]-di-μ-sulfato-κ3O:O,O′;κ3O,O′:O′] hexahydrate], [Eu2(C9H5N2O4)2(SO4)2(H2O)6]·6H2O}n, the 1H,3H-benzimidazol-3-ium-5,6-dicarboxylate ligand is protonated at the imidazole group (H2bdc). The EuIII ion is coordinated by nine O atoms from two H2bdc ligands, two sulfate anions and three water molecules, displaying a bicapped trigonal prismatic geometry. The carboxylate groups of the H2bdc ligands and the sulfate anions link the EuIII ions, forming a chain along [010]. These chains are further connected by N—H...O and O—H...O hydrogen bonds and π–π interactions between the imidazole and benzene rings [centroid–centroid distances = 3.997 (4), 3.829 (4) and 3.573 (4) Å] into a three-dimensional supramolecular network.